Nearly 2,000 people in the Seychelles have been infected with an incurable mosquito-borne disease that has spread to three Indian Ocean islands prompting health alerts, officials said.

Jules Gedeon, the Seychelles director for community health, said the number of people diagnosed with “chikungunya” was steadily rising since it was first reported in November and nearly 1,000 cases had been reported in January alone….Authorities in Madagascar and the overseas French territory of Reunion, where some 45,000 new cases have been reported since mid-December, have reported outbreaks.

Last week, the French government drafted 400 extra troops to help fight the mosquitoes that have been spreading the disease across Reunion since March.

On Madagascar, about 800 kilometers (500 miles) west of Reunion, a health official said Thursday that two more people had shown symptoms of the disease after dozens flocked to a hospital on the eastern side of the island with similar complaints in the past two weeks.